A vehicle electric power steering system has utilized a microprocessor that monitors a motor shaft position in the electric power steering system. The microprocessor, however, is turned off when the ignition of the vehicle is off (i.e., an ignition off state of the vehicle). Accordingly, if a vehicle operator turns the steering wheel during the ignition off state, when the microprocessor is subsequently turned on during an ignition on state, the microprocessor may not be able to accurate determine an absolute rotational position of the motor shaft.
Accordingly, it is desirable to provide a system and a method for determining an absolute rotational position of a rotatable shaft of a motor in an electric power steering system during an ignition off state of the vehicle.